Smoking just one cigarette can be injurious to the health of young adults. According to a research presented at the Canadian Cardiovascular Congress, smoking even one cigarette daily increases the stiffness of the arteries in young adults aged between 18 and 30 years by around 25 per cent. Stiff arteries increase resistance in blood vessels, making the heart work harder. Stella Daskalopoulou, internal medicine and vascular medicine specialist at McGill University Health Centre, who presented the research said, this increases the risk of heart diseases including an attack.<br/><br/>As part of the study, researchers compared arterial stiffness of young smokers, who smoke five to six cigarettes per day, to non-smokers using 'Applanation tonometry' method.<br/><br/>In this method, the subjects were introduced to a 'arterial stress test' which measures the arteries' response to the stress of exercise. The test is comparable to a cardiac stress test, which measures the heart's response to the stress of exercise.<br/>